This keeps happening to me, but nobody else has mentioned it. I haven't mentioned it, either, so that doesn't mean much. And it happened again last night.
I have a KitchenAid Classic, 4.5 quart bowl.
When I finished kneading some bread dough, I had trouble removing the bowl. The kneading action tightens the bowl, and I spent ten minutes trying to remove it. I even wrote myself a note before I began this time about which way to turn the bowl to get it off later.